Effective point-of-purchase displays utilizing an artificial or natural light source for powering a motion display have been successfully marketed for a number of years. These units typically comprise a solar cell mounted on reflective material or the like that is clipped directly onto a light source, such as a fluorescent or incandescent bulb, and are connected to a motor which turns a sign, mirror, or like display. Exemplary forms of such devices are v illustrated in U.S. Pat. Nos. 4,379,324 and 4,596,083.
While the assemblies disclosed in U.S. Pat. Nos. 4,379,324 and 4,596,083 are very worthwhile, there are some circumstances where different mounting of the solar cells is required, or where it is desirable to power a display other than one associated with a motor. According to the present invention, an energy converting assembly is provided which is particularly useful for point-of-purchase displays, which allows such desired results to be accomplished.
According to one aspect of the present invention, an energy converting assembly is provided which is specifically designed to mount solar cells in close proximity with a light source, is connected to a housing for the light source. The assembly specifically includes a particular mounting and spacing means to which a solar cell is mounted, which is connected to the housing and occupies the space between the housing and the light source (e.g., fluorescent bulb) so that the solar cell is held in close proximity to (e.g., in contact with) the light source. Preferably the mounting structure comprises a piece of sheet material, such as cardboard having a thickness of about 0.01-0.015 inches, with an undulating configuration (e.g., accordion, pleated, or serpentine), which occupies the space between the housing and the light source. Magnet strips can be used to connect the mounting means to the housing where the housing is metal. The solar cell is electrically connected to a display, and it powers the display.
Also according to the present invention, a display is provided which is effective for getting the attention of a potential purchaser, yet does not utilize a motor, and can be powered solely by a solar cell. This is accomplished by providing an array of light emitting diodes, each having a maximum current requirement of about 2 ma. Also, circuitry is provided for flashing the diodes, which circuitry has a minimum current drain. Only by utilizing a low current drain circuit and low current requirement LEDs is it possible to effectively power point-of-purchase display with solar cells utilizing an artificial light source without adversely restricting the light supply from the light source. The LEDs are preferably double heterojunction AlGaAs/GaAs LEDs, and may be red, yellow, or green. As many as twenty or thirty LEDs may be provided in a single array.
It is a primary object of the present invention to provide versatile and effective energy converting assemblies, particularly for point-of-purchase display use, powered by a light source preexisting at the point-of-purchase. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.